UML25 — Modeling Individuals

Why is instance specification not included?

Value specifications are mentioned as a means to model objects, but it would make more sense to use
instance specifications here instead, since that is the most common why to explicitly model objects in UML.
(An instance specification is not itself a value specification, though an instance value, which is a kind of
value specification, can reference an instance specification and an instance specification can have its value
specified by a value specification.)